For example, in general, a motor is used in a driving source, such as an electric vehicle, and the motor is controlled by an inverter device. A power semiconductor element, such as an insulated gate bipolar transistor (IGBT) or a power metal-oxide-semiconductor field-effect transistor (MOSFET), is used in the main circuit of the inverter device. Patent Literature 1 discloses an inverter bridge module in which a plurality of power semiconductor elements is connected to form a three-phase inverter bridge.
FIG. 17 is a diagram illustrating the structure of the inverter bridge module disclosed in Patent Literature 1. FIG. 17(a) is a perspective view illustrating the module and FIG. 17(b) is a perspective view illustrating the IGBT unit.
The inverter bridge module is formed by arranging sealed IGBT units 54a to 54f in a matrix of three rows and two columns on a heat sink 53 and connecting the IGBT units 54a to 54f to a P bus bar 51 and an N bus bar 52. A P terminal 51a and an N terminal 52a are exposed and protrude from the side surface of the unit.
In the inverter bridge module, the P bus bar 51 and the N bus bar 52 are arranged in parallel to each other to reduce line inductance.
In FIG. 17, reference numeral 55 indicates a first collector terminal, reference numeral 56 indicates a first emitter terminal, reference numeral 57 indicates a second collector terminal, and reference numeral 59 indicates a case.
Patent Literature 2 discloses a top-open-type assembly case in which discrete products of two sets of semiconductor modules are collectively accommodated such that a use number of semiconductor modules are aligned in a direction, thereby forming an integrated unit.
Patent Literature 3 discloses a printed circuit board which is assembled so as to overlap the main switching element.
Patent Literature 4 discloses a structure in which a semiconductor module is fixed to a heat sink or a radiator plate by screws which are inserted from a reinforcing beam into screw through holes of the semiconductor module through the reinforcing beam and a pressing leaf spring.